Fig. 1: Design and performance of all-perovskite tandem solar cells and modules.

a, Schematic and layer stack of all-perovskite tandem solar cells applied in this work. The champion tandem solar cells and modules employ sputtered indium tin oxide layers (thickness ~15 nm) and percolated Au thin films (nominal thickness ~1–2 nm) as a recombination layer, respectively. NBG and WBG are the abbreviations of the narrow and wide bandgap. b, Current density–voltage (J–V) curve and power conversion efficiency tracked at the maximum power point of the champion tandem devices for 5 min (in the inset). c, EQE of top and bottom subcell as well as the sum of both (grey symbolled line), and total absorbance calculated by 1 − reflectance (black solid line) for monolithic all-perovskite tandem solar cells. The light and dark blue regions denote the parasitic absorption and reflection losses, respectively. The corresponding losses in current density are provided. d, Schematic illustration of the two-terminal all-perovskite tandem solar module (not to scale) interconnection denoting the active area and scribing lines (for more details see Supplementary Fig. 21). The colour used for the module layers is the same as for tandem solar cells. e, J–V characteristics of individual tandem cell stripes of the module and the respective fill factors after a stepwise inclusion of cell stripes included in the measurement. f, Power, voltage and current at the maximum power point of the champion tandem solar module under continuous AM 1.5G illumination. g, Normalized power (Norm.), voltage and current at the maximum power point under temperature stress at 85 °C in nitrogen atmosphere. Panels a–c refer to tandem solar cells while panels d–g to tandem modules.